Low 3.8Published Jun 22, 2026

CVE-2026-8823User Manager can demote bot accounts to guest without bot-management permission

Updated under an hour ago (Oct 27, 2026, 1:00 PM ET)

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It affects Mattermost and 1 other product. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

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Every CVE for Mattermost

Exploited in the last 30 days

Mattermost versions 11.7.x <= 11.7.0, 10.11.x <= 10.11.17 fail to validate bot targets when demoting users to guests which allows a lower-privileged administrator to degrade arbitrary bot accounts via the standard demote-user API.. Mattermost Advisory ID: MMSA-2026-00669

CVSS: 3.8 LOW (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:L/A:L
Weakness (CWE): CWE-863
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: Mattermost
NVD analysis: Analyzed
Record last updated: Jun 22, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

Mattermost Mattermost mattermost:mattermost (from the name)	from 11.7.0 through 11.7.0; from 10.11.0 through 10.11.17; 11.8.0 not affected; 11.7.1 not affected; 10.11.18 not affected	CNA record
mattermost mattermost_server mattermost:mattermost_server	from 10.11.0 before 10.11.18; from 11.7.0 before 11.7.1	NVD

References

References

https://mattermost.com/security-updates	vendor-advisory

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.